In this review, we will be comparing R-25C and RP-504C II, two Passive Center Channel speakers by Klipsch.
Let's have a brief look at the main features
of Klipsch Reference R-25C and Klipsch RP-504C II first before getting into our more
detailed comparison.
| Key Specs | Klipsch Reference R-25C | Klipsch RP-504C II |
|---|
| Brand | Klipsch
United States · founded 1946 | Klipsch
United States · founded 1946 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | Tractrix Horn | 1" Tractrix Horn |
|---|
| Woofer | 2 x 5.25" Copper spun | 4 x 5.25" Cerametallic cone |
|---|
| Frequency response | 82-24K Hz | 50-25k Hz |
|---|
| Sensitivity | 98 dB | 96 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | up to 100 watts | up to 150 watts |
|---|
| Weight | 6.70kg / 14.7lbs | 16.50kg / 36.3lbs |
|---|
| Dimensions (H x W x D) | 7.25" x 18.75" x 7.25"
184 x 476 x 184mm | 6-15/16" x 32-3/16" x 15-1/8"
177.0 x 818.0 x 385.0mm |
|---|
What size room are the Klipsch Reference R-25C and Klipsch RP-504C II speakers good for?
The size of the room in which you are planning to use these loudspeakers is an important decision
factor. Here we have compared their suitability to various sizes of environments considering their size
and max power parameters:
| Listening Environment* |
Klipsch Reference R-25C |
Klipsch RP-504C II |
| Near-field |
Poor |
Poor |
| Small Room |
Average |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Average |
Average |
| Very Large Room |
Poor |
Poor |
(* Approximate Room sizes: Small < 100sq. ft / 9 m2,
Mid-size: 100-220 sq. ft / 9-20 m2, Large 220-400 sq. ft / 20-36 m2, Very Large: >
400 sq. ft / 36 m2.
Average Floor Height: 9" / 2.7m. Typical room sizes differ from country to country, and the actual
listening experience changes depending on floor height, room shape, surface materials, listening
position, speaker locations, etc.)
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both R-25C and RP-504C II are 2-way speakers.
Klipsch Reference R-25CKlipsch RP-504C II
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Klipsch Reference R-25C |
Klipsch RP-504C II |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 5.25-inch
|
4 x 5.25-inch
|
R-25C features a " LTS (Linear Travel Suspension) aluminum diaphragm Tractrix Horn Tweeter and 2 x 5.25" Copper spun Woofer with a Crossover frequency at 1800 Hz. On the other hand, the RP-504C II features a 1" titanium Tractrix Horn Tweeter and 4 x 5.25" Cerametallic cone Woofer with a Crossover frequency at 1950 Hz.
Frequency Response
R-25C has a frequency range of 82-24K Hz whereas RP-504C II has a frequency range of 50-25k Hz. With a minimum frequency of 50Hz, the RP-504C II can go significantly deeper on the low side and provide stronger bass compared to the R-25C's min frequency of 82Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Center Channel class in our database.
Low Frequency
Center Channel Speakers
Neither pair reaches down to 20Hz, the usual definition of full-range, which is normal for speakers of this size. If you want the bottom octave for movies or bass-heavy music, add a subwoofer to whichever you choose. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
R-25C and RP-504C II have the same Impedance of 8 ohms but where they differ is the sensitivity levels. R-25C sensitivity is rated at 98 dB and the RP-504C II's is at 96 dB. This 2 dB difference makes the Klipsch Reference R-25C a more sensitive speaker compared to Klipsch RP-504C II, hence will play louder with the same amount of watts.
Sensitivity
Center Channel Speakers
Power Range
Power
range is the range of input power in watts RMS that a loudspeaker is designed to handle. Staying
within that range gives nominal performance; driving the speaker beyond its maximum wattage can damage it.
RP-504C II can handle a max power of 150 watts RMS, whereas R-25C has a max power handling value of 100 watts RMS, 50 watts less than the RP-504C II.
Note that higher power handling does not make a speaker louder: that depends mainly on
sensitivity and impedance. The calculator below shows how loud each of these actually plays
on a real amplifier.
Which plays louder on your amplifier?
Starting with a popular amplifier - change it to the one you own, or any you are
considering, and watch both numbers move.
Input Type and Bi-Amping / Bi-Wiring
R-25C features Binding post type posts and RP-504C II has a Binding post type posts. None of these speakers feature bi-amping/bi-wiring.
Klipsch Reference R-25C's Binding post terminals
Klipsch RP-504C II's Binding post terminals
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Klipsch Reference R-25C's and Klipsch RP-504C II's external dimensions. Klipsch Reference R-25C has external dimensions of 184 x 476 x 184mm (7.25 x 18.75 x 7.25-inch) whereas Klipsch RP-504C II has external dimensions of 177.0 x 818.0 x 385.0mm (6-15/16 x 32-3/16 x 15-1/8inch).
Klipsch Reference R-25C is 342mm narrower and 201mm less deeper than Klipsch RP-504C II but it is also 7mm taller.
Below you can see the front view size comparison of Klipsch Reference R-25C and Klipsch RP-504C II in scale.
Comparison image of Klipsch Reference R-25C and Klipsch RP-504C II Size and External Dimensions
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the Klipsch Reference R-25C is approximately 876.0cm2 / 135.8inch2 and base area of the Klipsch RP-504C II is approximately 3149.3cm2 / 488.1inch2. The R-25C requires 72% less surface area than the RP-504C II which gives it a small advantage on placement in tight spaces.
Weight Comparison The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The Klipsch Reference R-25C weighs 6.70kg / 14.7lbs and the Klipsch RP-504C II weighs 16.50kg / 36.3lbs. This makes the RP-504C II 146% heavier than the R-25C.
Here is a comparison of how R-25C and RP-504C II's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
What's in the Box of Klipsch Reference R-25C?
Here are the items that are included inside the box of R-25C:
- Center-channel loudspeaker
- Grille
- User Manual
- Important Safety Instructions
- Warranty Information
What's in the Box of Klipsch RP-504C II?
Here are the items that come with the RP-504C II:
- Center channel loudspeaker
- Grille
- User Manual
- Important Safety Instructions
- Warranty Information
 Sensitivity |
98 dB
vs
96 dB
|
Play louder with same amount of amplification power |
 Base Surface Area |
876cm2
vs
3149cm2
|
Takes less floor space |
 Price per pair* |
129USD
vs
799USD
|
costs less (*prices may change depending on the seller, location and time) |
 Max Input Power |
150 watts
vs
100 watts
|
Handle more power from your amplifier |
 Number of Woofers |
4
vs
2
|
More woofers |
|
Low Frequency Response |
50 Hz
vs
82 Hz
|
Generates deeper bass |
 High Frequency Response |
25k Hz
vs
24k Hz
|
Generates higher frequency |
 Height |
177mm
vs
184mm
|
Easier to fit in smaller spaces |
| General |
Klipsch Reference R-25C |
Klipsch Reference Premiere RP-504C II |
| Brand |
Klipsch |
Klipsch |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
up to 100 watts |
up to 150 watts |
| Sensitivity |
98 dB |
96 dB |
| Impedance |
8 ohms |
8 ohms |
| Frequency Response |
82-24K Hz |
50-25k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
4 |
| Woofer Size |
5.25" |
5.25" |
| Woofer Composition |
Copper spun |
Cerametallic cone |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
- |
1" |
| Tweeter Type |
Tractrix Horn |
Tractrix Horn |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
1800 Hz |
1950 Hz |
| Firing Direction |
n/a |
rear |
Physical Specs |
|
|
| Height |
184.0mm (7.2") |
177.0mm (7") |
| Width |
476.0mm (18.7") |
818.0mm (32.2") |
| Depth |
184.0mm (7.2") |
385.0mm (15.2") |
| Weight |
6.70kg (14.7lbs) |
16.50kg (36.3lbs) |
| Enclosure |
Sealed |
Bass Reflex |
| Finish |
Polymer Veneer |
MDF/Wood-grain vinyl |
| Available Colors |
Black |
Walnut, Black |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
No |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |
These sit in different price classes - Klipsch RP-504C II costs roughly 6.2x what Klipsch Reference R-25C does. Expect it to lead on paper; the question is whether the gap is audible enough in your room to be worth it.
| Area | Better | Why |
|---|
| Bass | B | Klipsch RP-504C II digs deeper - 50Hz against 82Hz. |
| Amplifier needs | A | Klipsch Reference R-25C is more sensitive (98dB vs 96dB), so it goes louder on the same amplifier. |
| Headroom | B | Klipsch RP-504C II takes more power (150W vs 100W) - more in hand in a big room. |
| Size | depends | Klipsch Reference R-25C is easier to place; Klipsch RP-504C II is bigger, which usually goes with fuller bass. Your room decides. |
| Cabinet | depends | Sealed vs Ported. Sealed is tighter and happier near a wall; ported digs lower but wants space behind it. |
| Expandability | depends | Neither adds bi-amping, a sub output or height drivers. Klipsch RP-504C II sits in a wider range (10 models), so a matched surround system is easier later. |
| Price | A | Klipsch Reference R-25C is cheaper - $129 against $799, about 84% less; arguably a different class. |
A Klipsch Reference R-25C B Klipsch RP-504C II
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Klipsch RP-504C II is ahead, but only on 1 of the measured areas, and it costs about 6.2x the price. That is a lot of money for a narrow margin on paper - Klipsch Reference R-25C looks like the sensible buy unless something else about the Klipsch RP-504C II appeals to you. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 82Hz anyway, which makes the cheaper Klipsch Reference R-25C much easier to justify. In a large or open-plan room, Klipsch RP-504C II has the cabinet volume to fill it more easily; in a small room, near a wall or at desk distance, Klipsch Reference R-25C is the easier speaker to get right.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.